This invention pertains to fuel cell systems and, in particular, to fuel cell systems adapted to inhibit electyrolyte loss.
In the operation of fuel cells, it is usual that the fuel cell will lose electrolyte due to the large volume of process gases which contact the electrolyte during fuel cell operation. Electrolyte may also be lost via other mechanisms, such as reactions with cell components, corrosion and creepage. This occurrence of electrolyte loss has resulted in a variety of techniques for replenishing lost electrolyte. In these techniques electrolyte is usually supplied to the fuel cell by introducing fresh electrolyte from an electrolyte supply.
U.S. Pat. No. 3,634,139 discloses one system wherein internal pools coupled to an external reservoir serve as the electrolyte supply. In U.S. Pat. No. 4,038,463, a layer adjacent the catalyst layer of a fuel cell electrode is used as an electrolyte reservoir and forms the electrolyte supply. Finally, in U.S. patent application Ser. No. 327,970, assigned to the same assignee hereof, electrolyte is stored in electrode channels adjacent the fuel cell electrolyte matrix and electrolyte may be added periodically to the cell to fill the channels.
While these procedures have provided some degree of success in maintaining fuel cell electrolyte levels, research is still being conducted to develop alternative techniques.
It is an object of the present invention to provide a fuel cell system and method adapted to suppress or inhibit electrolyte loss.
It is a further object of the present invention to provide a fuel cell system and method adapted to replenish electrolyte lost by the cell.